1. Field of the Invention
The present invention relates generally to apparatus and methods for wrapping articles, particularly bundles of newspapers, and more specifically, relates to an apparatus with an integrated bundleturner for bottom-wrapping or three-sided wrapping of bundles, and a method for wrapping bundles.
2. Description of the Prior Art
It is common in the printing and publishing industries to bundle and tie together stacks of newspapers or other publications to aid in shipping, transport, and storage. Typically, it is desirable that these bundles be wrapped or otherwise covered for protection, often by simply inserting a length of paper under the bottom surface of the bundle, known as bottom-wrapping, or by covering the bundle on three sides, known as three-way wrapping, which better protects the bundle from wetness or soiling. Bottomwrapping and three-way wrapping machines have been devised which dispense a pre-fed sheet of durable paper of predetermined length from a roll of paper. However, generally such machines are capable of performing only a single type of wrapping technique, that is, either bottomwrapping or three-way wrapping, or require an attachment or accessory to allow the machine to perform both functions. Most wrapping machines require that the paper web be upwardly fed, often through a paper guide assembly and then maintained in that vertical orientation generally in the path of the bundle, either by gripping the upper end of the paper web or by creasing or otherwise manipulating the paper to allow it to stand upright and not fold down upon itself.
For instance, U.S. Pat. No. 5,274,983 to Sjogren et al discloses an apparatus for wrapping a bundle, but requires that the wrapping sheet be shaped in a predetermined manner, preferably by creasing, to provide sufficient rigidity to permit the sheet to be self-supporting. U.S. Pat. No. 5,009,055 to Simmons discloses an apparatus for wrapping an article on three sides, which provides a means to grip the an upper margin of the wrapping material and upwardly guide the material into the path of the bundle. Wright et al in U.S. Pat. No. 3,716,960 show an accessory attachment for a bottom wrap inserter that converts it into a three-sided wrap inserter.
Other patents relating to wrapping or bundling devices include U.S. Pat. No. 4,991,376 to Backman, U.S. Pat. No. 5,447,008 to Martin-Cocher, U.S. Pat. No. 4,531,343 to Wood, U.S. Pat. No. 4,726,172 to Widenback, U.S. Pat. No. 4,993,203 to Haloila, U.S. Pat. No. 5,218,813 to Seidel, and U.S. Pat. No. 5,636,496 to Pietila et al.
The above wrapping machines generally employ means for cutting the paper or plastic web between successive wrapping actions. In addition to these means, a variety of such cutting mechanisms have been developed for use on bundle wrapping machines, and for other devices which require the cutting or shearing of a material web. For example, Singer in U.S. Pat. No. 4,328,896 discloses a slitting machine for separating the overlapped portions of a web of continuously laminated articles, where the cutting means consists of two oppositely facing blades mounted to a carriage. U.S. Pat. No. 5,216,873 to Ratzlaff et al reveals a wrapper cutoff mechanism for round balers, which employs a movable knife and stationary anvil. Jennings et al in U.S. Pat. Nos. 5,448,873 and 5,319,899 disclose a net knife for a round baler which has a plurality of side-by-side scalloped shaped sections on one edge of the blade for cleanly severing net material.
Other web cutting mechanisms are disclosed in U.S. Pat. No. 4,852,442 to Pottorff U.S. Pat. No. 5,259,167 to Underhill et al, U.S. Pat. No. 3,680,610 to Lindgren, and U.S. Pat. No. 5,375,496 to Peru et al.
The above cutting mechanisms generally utilize dangerously sharp, single-sided blades, which require that after making a cut, the blade carriage reverse back upon itself for cutting the next length of paper for the next bundle, thus requiring more time between successive wrapping actions. In addition, the wrapping machine must be equipped so that the paper web is suitably tensioned to allow a clean cutting action. These cutting mechanisms also require greater attention to maintenance and handling of the blade and accessory components.
Thus, a need exists for an improved bundlewrapping machine adapted to function as both a bottomwrapper or a three-way wrapper and which provides a simpler, more effective means for maintaining the paper web in its vertical orientation prior to wrapping, and which utilizes an improved, more efficient cutting mechanism for quickly and cleanly cutting the paper web.
In addition, it would be desirable to integrate a bundleturning device into a bundlewrapping machine: bundleturning devices are commonly used in the print and publishing industry to vary the orientation of the article on a conveyor system prior to or after wrapping. Bundleturners are generally separate pieces of equipment which must be placed next to or in the vicinity of the wrapping machines, thus requiring more space and of course, maintenance of their own components. Thus, a need exists for a wrapping machine that includes a bundleturning assembly as an integral part of its design.
The present invention resolves these and other problems commonly associated with the prior art bundlewrapping machines by providing an apparatus capable of both bottomwrapping and three-way wrapping of a bundle, which includes an improved, more efficient cutting assembly and which incorporates a bundleturning assembly into the wrapping machine.